Radiation therapy involves medical procedures that selectively expose certain areas of a human body, such as cancerous tumors, to high doses of radiation. The intent of the radiation therapy is to irradiate the targeted biological tissue such that the harmful tissue is destroyed. During a radiation therapy, a radiation source may be rotated around a patient to deliver radiation from different angles at target region inside the patient. The radiation source may be mounted on an arm or a ring gantry.
Also, radiation may be used for imaging purposes. For example, a computed tomography (CT) machine has a radiation source configured to rotate around a patient while delivering imaging radiation from different gantry angles around the patient.
In both treatment and imaging procedures, it may be desirable to monitor positions of different parts of the patient. Thus, applicant of the subject application determines that it may be desirable to provide a patient monitoring system that can simultaneously monitor different parts of a patient.